IPV6_MTU(2const)                                              IPV6_MTU(2const)

NAME
       IPV6_MTU - path maximum transmission unit size

LIBRARY
       Standard C library (libc, -lc)

SYNOPSIS
       #include <netinet/in.h>  /* Definition of IP* constants */
       #include <sys/socket.h>

       int setsockopt(int sockfd, IPPROTO_IPV6, IPV6_MTU,
                      const int *val, sizeof(int));
       int getsockopt(int sockfd, IPPROTO_IPV6, IPV6_MTU,
                      int *val, sizeof(int));

DESCRIPTION
       getsockopt():
              Retrieve the current known path MTU of the current socket.
              Valid only when the socket has been connected.

       setsockopt():
              Set the MTU to be used for the socket.  The MTU is limited by
              the device MTU or the path MTU when path MTU discovery is
              enabled.

ERRORS
       See IPPROTO_IPV6(2const).  See setsockopt(2).  See ipv6(7).

SEE ALSO
       IPPROTO_IPV6(2const), setsockopt(2), ipv6(7)

Linux man-pages 6.17              2025-12-02                  IPV6_MTU(2const)